PORT ST. LUCIE – The starting rotation the Mets will take into the season moved closer into focus yesterday.

Pedro Martinez stayed on track for his spring debut Thursday with a high-intensity session of batting practice in the morning, then Mike Pelfrey strengthened his bid for Orlando Hernandez’s No. 5 spot in the afternoon.

Following up on a strong first start last week against the Tigers, Pelfrey had his sinker working. He scattered just two hits in three scoreless innings of a 3-2 Grapefruit League victory over the Braves.

It also couldn’t have hurt the big right-hander’s case that his breezy outing came on the same day Hernandez was scratched from a scheduled BP shift because of discomfort in his right foot.

“Like I’ve said, I just want to make their decision difficult,” Pelfrey said when asked about fighting for Hernandez’s spot. “I was a little better [yesterday], and that’s the goal – get better every day.”

The Triple-A lineup the Braves brought down from Disney World could do little more than break their bats against Pelfrey’s 91 mph sinker. He left some change ups high in the strike zone in the first, leading to a single and two fly balls, but started getting inside and sawing off Atlanta hitters over the next two innings.

Pelfrey was so crisp he had to go into a nearby bullpen afterward and throw 30 more pitches to reach his target for the day.

“I don’t judge my [pitchers] until they get some wind under their sails, but Pelfrey looks like he’s starting to get into a little early rhythm,” Willie Randolph said.

Randolph hasn’t been able to say the same about Hernandez because the 40-something Cuban – who insists he won’t accept a bullpen assignment – isn’t able to do much because of ligament and bunion issues in his foot.

Randolph said “El Duque” is now scheduled to throw BP tomorrow and could make his mound debut this weekend, but the manager didn’t sound confident. In fact, Randolph sounded as if his patience with Hernandez is wearing thin.

“He has to get on the mound,” Randolph said. “We’re not going to go into the season with guys only giving us five innings. If he’s not ready, it is what it is.”

Luckily for Randolph, the Mets don’t have to hurry their decision because days off mean a fifth starter won’t be necessary until April 12.

Pelfrey certainly isn’t overconfident, even with his five scoreless innings so far.

“I would never count El Duque out,” Pelfrey said. “He could probably go without all throwing all spring training, then go eight innings [in his first start of the season].”

Martinez, meanwhile, provided a reassuring sight for the injury-ravaged Mets with an intense, 45-pitch BP session.

With starter Brian Schneider catching, Pedro faced rehabbing outfielder Ben Johnson and rookie-ball prospects Ruben Tejada, Ezequiel Carrera, Gregory Veloz and Daniel Murphy. Johnson was the only one to make much contact against Martinez, who had his fastball moving around in midseason form.

“I pushed it a little bit,” Martinez said of his stamina. “I kind of let it go a little more and had better command. I felt a lot more comfortable.”

So comfortable that Martinez doesn’t mind all that much having to bus 80 miles north to Viera, Fla., on Thursday to face the Nationals.

“It’s too bad I have to go on the road,” Martinez said. “But if they need me to go up there to pitch my two innings, I’ll take the trip to Viera.”